I'm on my second DI due to this issue. I thought it was a phone issue but through research on here and other boards see it's a sofeware/app issue. I use yahoo mail as my sole mail/pop account.
My replacement phone started to get the low memory message recently, seems like 2weeks and it strats happening. It could be related to me changing setting frome default to 30days and no limit on messages. However, in preparation to wipe it, I backed everything up. Then I tried something. I didn't wipe the phone and I installed K9 as suggested here and a strange thing happened. Everything stared to work fine again...it's as if installing K9 undid something that was causing the memory prob...
So I'm still using HTC mail, I just have a duplicate of the mail in K9. I have polling turned off on k9 so I don't end up with a ton of unneeded mail.
I'll report back if anything changes. Thoughts?